Bar hanger and mounting clip assembly

ABSTRACT

A bar hanger and mounting clip assembly for securing an electrical box between two opposed Tee bar elements in a ceiling structure is provided which comprises a spanning bar which spans between the two opposed Tee bar elements; first and second clips at opposed ends of the spanning bar for attaching the spanning bar to the two opposed Tee bar elements; an electrical box; and a mounting clip for securing the electrical box to the spanning bar, the mounting clip including a tension leg for initially holding the electrical box in position on the spanning bar before the clip is securely fastened to the electrical box.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority under 35 U.S.C. §119(e) toprovisional patent application serial No. 60/132,561 filed May 5, 1999,entitled “Bar Hanger and Mounting Clip Assembly,” the entire disclosureof which is incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates generally to the art of supportclips and brackets and, more particularly, to a box hanger and mountingclip assembly for securing an electrical box between two Tee bars or thelike.

BACKGROUND OF THE INVENTION

[0003] Heretofore, electrical junction boxes have been supported belowgrid ceilings using cumbersome support structures that are relativelydifficult and costly to install. Prior methods of support involve, forexample, the use of separate support members such as angle irons orunistruts which are cut to a required length at the job site. Thesesupport members are positioned on top of or above the grid ceiling atspecified fixture support locations, and then they are anchored to thebuilding superstructure by overhead load wires. Wherever an electricalfeed is required, an electrical box must be installed along with theanchored support member. For this purpose, commercially availablemounting rails or spanning bars that fasten to the Tee bars of the gridceiling system are commonly used. Spanning bars are installed across theindividual grids of the ceiling's Tee bar grid structure and permit theelectrical box to easily be located with selected grids. Sometimes aload wire is dropped directly to the spanning bar and attached by meansof a wire clip, however, without independent support the load carryingcapacity of such an arrangement is limited.

[0004] Acoustical “Tee Bar” electrical box hangers have been widelyemployed, in the construction of ceilings, and particularly suspended ordrop ceilings. One example is the CADDY® 512 or 512A box hanger. CADDY®is a registered trademark of Erico, Inc. of Solon, Ohio. The hangercomprises two clips riveted to the ends of a spanning bar which snap onthe bulb end of the stem of the Tee bar. The electrical box is held tothe spanning bar by a spring finger clip embracing the bar which issecured to the back of the electrical box by a threaded fastener. Tomount the clip to the box, a knock-out must be removed from the box. Thespanning bar is rectangular and edgewise to the load, with the springfinger clip including a bent portion extending over the spanning bar andwith a tab of the clip being inserted into the knock-out therebyengaging an inside surface of the back of the electrical box. Theportion of the clip which is secured to the back of the electrical boxby a threaded fastener requires lining up a threaded hole in the clipwith a mating hole in the electrical box. The 512A hanger includesslotted intermediate brackets between the ends of the spanning bar andTee bar clips. The spanning bar is secured to the brackets by threadedclamp fasteners.

[0005] As one skilled in the art can see, the above 512 box hangerassembly has a number of disadvantages. From the perspective of theinstaller, screws and other detached pieces of a multipart assembly canbe discouraging. To install the 512 clip assembly to the electrical box,each and every piece of the entire assembly, with the tab of the clipinserted into the knock-out and the threaded hole lined up with themating hole in the electrical box, must be carefully held together bythe installer while the screw is installed through the box and into theclip. This method is very cumbersome and can be dangerous. One has torealize that this work is usually done on a ladder or scaffold and lostparts or forgotten special tools can be a real time wasting problemwhich can induce the installer into jury rigged unsafe shortcuts. Anyslip of the bar or the assembly can result in the assembly losing itslocation in reference to the box. Moreover, all buildings vibrate, andsuspended wire or chain drop ceilings are susceptible to specialharmonics. A need therefore exists for a bar hanger and mounting clipassembly, having all the flexibility and advantages of the multipart 512clip assembly, yet does not include the cumbersome disadvantagesdescribed above.

SUMMARY OF THE INVENTION

[0006] The present invention fulfills this need by providing a loadbearing bar hanger and mounting clip assembly: that eliminates the needfor the installer to carefully hold together each and every piece of theentire assembly, with the tab of the clip inserted into the knockout andthe threaded hole lined up with the mating hole in the electrical box,while the screw fastener is installed through the box and into the clip;that eliminates the need for separate support structures; that cansatisfy most load specifications; that offers a savings in labor andmaterials as compared to clip assemblies heretofore used; that can beinstalled using commercially available spanning bars; that can beinstalled relatively easily by providing a tension leg for temporarilyholding the assembly in position on the electrical box as hardware isinstalled; that provides a means to center the point of attachment for asupport wire to avoid cocked mounting of connected electrical devices;that substantially covers a knock-out opening of the electrical box topromote NEC compliance of the overall assembly; that is readily adaptedfor use at electrical feed locations; and that has added versatility sothat it can be used to accommodate a wide variety of differentstructural environments and load wire configurations.

[0007] These objects and advantages are accomplished through a barhanger and mounting clip assembly comprising a clip for securing anelectrical box to a spanning bar, the clip comprising a first generallyhorizontally disposed flat portion engageable with an outer surface ofthe electrical box; an inverted generally U-shaped portion, attached tothe first flat portion, sufficiently sized for receiving the spanningbar; a second generally horizontally disposed flat portion, attached tothe inverted U-shaped portion, specifically configured to be receivedthrough a box knock-out opening formed in a wall of the electrical box,the second flat portion engaging an inner surface of the wall of theelectrical box; and an initial holding means in the form of a tensionleg for initially holding the clip in position on the electrical boxbefore the clip is securely fastened to the electrical box. In thisparticular embodiment of the present invention, the tension legcomprises a first portion extending generally upwardly from the secondflat portion of the clip; a second portion extending laterally outwardlyand downwardly from the first portion of the tension leg; and a thirdportion extending generally upwardly from a lower edge of the secondportion of the tension leg. The first, second and third portions of thetension leg and the second flat portion of the clip cooperate to form achannel means for receiving a peripheral edge of the knock-out openingin the wall of the electrical box. The distance of separation betweenthe lower edge of the second portion of the tension leg and the secondflat portion of the clip is preferably less than the thickness of thewall of the electrical box so that the lower edge resiliently engagesthe wall of the electrical box when the wall is received therein. Theclip may further comprise a load wire attachment means for receiving andengaging one or more load wires. The load wire attachment meanspreferably comprises a generally upwardly extending wire attachment armand at least one wire attachment hole formed in the arm for receivingone or more load wires. The wire attachment arm preferably extendsgenerally upwardly from the inverted U-shaped portion of the clip. Theclip substantially covers the knock-out opening in the electrical boxonce installed.

[0008] In another embodiment of the present invention, a bar hanger andmounting clip assembly for securing an electrical box between twoopposed Tee bar elements in a ceiling structure is provided whichcomprises a spanning bar which spans between the two opposed Tee barelements; first and second clips at opposed ends of the spanning bar forattaching the spanning bar to the two opposed Tee bar elements; anelectrical box; and a mounting clip for securing the electrical box tothe spanning bar, the mounting clip including initial holding means forinitially holding the electrical box in position on the spanning barbefore the clip is securely fastened to the electrical box. The mountingclip preferably comprises a first generally horizontally disposed flatportion engageable with an outer surface of the electrical box; aninverted generally U-shaped portion, attached to the first flat portion,sufficiently sized for receiving the spanning bar; and a secondgenerally horizontally disposed flat portion, attached to the invertedU-shaped portion, specifically configured to be received through a boxknock-out opening formed in a wall of the electrical box, the secondflat portion engaging an inner surface of the wall of said electricalbox. The initial holding means preferably comprises a tension leg whichincludes a first portion extending generally upwardly from the secondflat portion of the mounting clip; a second portion extending laterallyoutwardly and downwardly from the first portion of the tension leg; anda third portion extending generally upwardly from a lower edge of thesecond portion of said tension leg. The first, second and third portionsof the tension leg and the second flat portion of the mounting clipcooperate to form a channel means for receiving a peripheral edge of theknock-out opening in the wall of said electrical box. The distance ofseparation between the lower edge of the second portion of the tensionleg and the second flat portion of the mounting clip is less than thethickness of the wall of the electrical box so that the lower edgeresiliently engages the wall of the electrical box when the wall isreceived therein. The clip may further comprise a load wire attachmentmeans for receiving and engaging one or more load wires which preferablycomprises a generally upwardly extending wire attachment arm and atleast one wire attachment hole formed in the arm for receiving the oneor more load wires. The wire attachment arm preferably extends generallyupwardly from the inverted U-shaped portion of the clip. The clipsubstantially covers the knock-out opening in the electrical box onceinstalled.

[0009] Other objects, features, and advantages of the present inventionwill become more fully apparent from the following description andappended claims, or may be learned by the practice of the invention asset forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more fully understand the manner in which theabove-recited and other advantages and objects of the invention areobtained, a more particular description of the invention will berendered by reference to a specific preferred embodiment(s) thereofwhich is/are illustrated in the appended drawings. Note particularlythat the appended drawings are not necessarily drawn to scale.Understanding that these drawings depict only typical embodiments of theinvention and are not therefore to be considered to be limiting of itsscope, the invention and its presently understood best mode for makingand using the same will be described and explained with additionalspecificity and detail through the use of the accompanying drawings inwhich:

[0011]FIG. 1 is a top perspective view of a bar hanger and mounting clipassembly in accordance with the present invention installed at anelectrical feed location on a spanning bar with an electrical boxattached thereto;

[0012]FIG. 2 is a bottom perspective view of the bar hanger and mountingclip assembly of FIG. 1;

[0013]FIG. 3 is an exploded top perspective view of the bar hanger andmounting clip assembly of FIG. 1;

[0014]FIG. 4 is a top plan view of the bar hanger and mounting clipassembly of FIG. 1;

[0015]FIG. 5 is a top plan view of the mounting clip shown in FIG. 1;and

[0016]FIG. 6 is a side elevational view of the mounting clip shown inFIG. 1.

DETAILED DESCRIPTION

[0017] The present invention may be used with a grid ceiling systemsuspended below a structural ceiling. A grid ceiling typically has a Teebar grid which hangs from the room's structural ceiling by drop wiresand which supports ceiling tiles, typically acoustical tiles, at adesired height from the floor. The present invention preferably makesuse of spanning bars conventionally used to install electrical boxes orother objects in the grid ceiling.

[0018] Referring now to the drawings, a representative bar hanger andmounting clip assembly for securing an object such as an electrical boxB between two Tee bars (not shown) or the like, embodying variousfeatures the present invention, is generally indicated throughout thefigures by reference character 10. Electrical box B is of a conventionaltype, and includes a generally rectangular peripheral side wall havingan open front end; a rear end that is closed by a rear wall 11; and oneor more knock-outs 12. Rear wall 11 includes inner and outer surfaces13, 14. FIGS. 1, 2 and 4 show a mounting clip 15 installed on a spanningbar 16 which spans two opposed Tee bar elements (not shown) of a gridceiling system. The spanning bar 16, which is typically of generallyrectangular cross-section, may be attached to the grid's Tee bars bymeans of clips 17, which, together with the spanning bar, are standard,commercially available products. Clip assembly 10 holds the electricalbox B to provide an electrical feed location in the grid ceiling system.Two degrees of adjustment are provided for positioning the clip assembly10 within the ceiling grid. One degree of adjustment is provided bysliding the spanning bar 16 along the Tee bar elements and anotherdegree of adjustment is provided by sliding the clip assembly 10 alongthe spanning bar 16 itself.

[0019] For economical manufacture, clip 15 is stamped from a flat sheetmetal blank, preferably heat-treated and spring-tempered steel, and isbent and integrally formed in accordance with a main bending profile, asbest shown in FIG. 6. As viewed in FIG. 6 from left to right, clip 15includes a first generally horizontally disposed flat portion 18engageable with the outer surface 14 of the electrical box B; aninverted generally U-shaped portion 19 sufficiently sized for receivingthe spanning bar 16; and a second generally horizontally disposed flatportion 20 specifically configured to be received through a boxknock-out 12 for engaging the inner surface 13 of the electrical box B.The second flat portion 20, however, may include a pair of substantiallyparallel tabs 21.

[0020] In a preferred embodiment, as best viewed in FIG. 6, clip 15includes a means for preliminarily or initially holding the clip 15 inposition on the electrical box B as hardware is installed before theclip 15 is securely fastened to the box B. The initial holding meanspreferably comprises a tension leg 25 which, as viewed in FIG. 6,includes a first portion 26 extending generally upwardly from the secondflat portion 20 of clip 15; a second portion 27 extending laterallyoutwardly and downwardly from the first portion 26 toward the secondflat portion 20; and a third portion 28 extending generally upwardlyfrom a lower edge 29 of the second portion 27. The portions 26, 27, 28of tension leg 25 and the second flat portion 20 of clip 15 cooperate toform a channel means 30 which is adapted to receive a peripheral edge 31of a knock-out 12 in the wall 11 of the electrical box B (FIGS. 1, 2 and4). The distance of separation between the lower edge 29 of the secondportion 27 of tension leg 25 and the second flat portion 20 of clip 15is preferably less than the thickness of the peripheral edge 31 ofknock-out 12 in rear wall 11 of box B so that the lower edge 29resiliently engages and firmly grips the wall 11 of the box B when it isreceived therein thereby initially securing the box B in a fixedposition relative to the clip 15. As one skilled in the art willappreciate, this eliminates the need for the installer to carefully holdtogether by hand each and every piece of the entire assembly while thebox B is securely fastened to the clip and while hardware is installedin or on the box. Moreover, one will also appreciate, as best view inFIG. 4, that the clip 15 once installed substantially covers theknock-out opening 12 of the electrical box B which promotes NECcompliance of the overall assembly with respect to openings created whena knock-out is removed. Furthermore, a skilled artisan will alsoappreciate that there may be more than one tension leg 25 and that thetension leg 25 may be formed at other locations on the clip 15 so that,for example, the leg 25 initially engages the spanning bar 16 therebyproviding substantially the same benefit.

[0021] The clip 15 may further include a load wire attachment means toreceive and engage one or more load wires 32 which are anchored tooverhead structural elements of the building. The load wire attachmentmeans preferably includes a generally upwardly extending wire attachmentarm 33, as best seen in FIG. 6, extending upwardly from the invertedU-shaped portion 19 of clip 15. At least one wire attachment hole 34 informed in arm 33 to receive the load wire(s) 32. By having the wireattachment arm 33 extend upwardly from the inverted U-shaped portion 19,one skilled in the art can see that the point of attachment for the loadwire(s) 32 is generally centered in reference to the box B and thespanning bar 16. This preferred configuration assists in maintaining theattached device(s) generally square to the ceiling because the load isapplied at generally the center of the electrical box B and the spanningbar 16. This is definitely an advantage over the 512 prior art assemblywhich has the attachment point of the load wire off center which tendsto cause twisting of the box under the load of the device mounted to thebox. Accordingly, the preferred wire attachment means of the presentinvention provides a means to center the point of attachment for theload wire 32 to avoid cocked mounting of connected electrical devices.

[0022] It should be understood that the load wire configurationillustrated in FIGS. 1 and 3 is illustrative only. The actual load wirescheme used for a particular installation will be determined by localvarious requirements such as building codes, the structuralconfiguration of the installation, and the presence or absence ofobstructions, such as heating/cooling ducts in the vicinity of thesupport locations. For example, two or more load wires, which may besplayed relative one another, can be attached to the wire attachmenthole 34 to add lateral support which may be required by code.

[0023] As mentioned above, the electrical box B is held to the spanningbar 16 by clip 15 which embraces the bar 16. To securely fasten the clip15 to the box B, the clip 15 includes inverted U-shaped portion 19extending over the spanning bar 16 and a pair of tabs 21 which areinserted into a knock-out opening 12 thereby engaging an inside surface13 of the rear wall 11 of the electrical box B. The first flat portion18 of clip 15 is securely fastened or attached to the outer surface 14of the electrical box B by a threaded fastener such as a screw 22. Screw22 is received through the open end of box B, through a mating hole 23in the rear wall of the box B, whereupon it threadingly engages athreaded hole 24 in the first flat portion 18. This requires lining upthreaded hole 24 in the clip 15 with the mating hole 23 in theelectrical box B. As indicated above, this task is made much easier byutilization of the initial holding means 25.

[0024] In a permissively variable sequence, installation of the clipassembly 10 for an electrical feed location includes the followingsteps. First, a knock-out 12 must be removed from the box B. Next,locate the spanning bar 16 within the grid ceiling system near the feedlocation in a conventional manner. The clip 15 is then placed over thespanning bar 16 such that the spanning bar 16 is received and engaged inthe inverted U-shaped portion 19 of clip 15. Before the electrical box Bis securely fastened to the clip 15, the pair of tabs 21 are insertedinto the knock-out opening 12 thereby engaging the inside surface 13 ofthe rear wall 11 of the electrical box B. At generally the same time,channel means 30 receives the peripheral edge 31 of knock-out 12 in thewall 11 of the electrical box B wherein the lower edge 29 of tension leg25 resiliently engages and firmly grips the wall 11 of the box B therebyinitially securing the box B in a fixed position relative to the clip15. Still, before the electrical box B is securely fastened to the clip15, the clip and electrical box B can be moved in either direction alongthe spanning bar 16 to locate, along with further adjustments of thespanning bar 16 on the Tee bar elements, the electrical box B in thedesire position. Next, the clip 15 is securely fastened to theelectrical box B as described above. Once the electrical box B issecurely fastened to the clip 15, the load wire(s) 32 are installed andattached to the clip 15 in whatever configuration is required. Theelectrical box B is then wired in a conventional manner and theelectrical devices are installed.

[0025] Although a preferred embodiment(s) of the present invention hasbeen described above by way of example, it will be understood by thoseskilled in the field that modifications may be made to the disclosedembodiment(s).

What is claimed is:
 1. A clip for securing an electrical box to a spanning bar, said clip comprising: (a) a first generally horizontally disposed flat portion engageable with an outer surface of said electrical box; (b) an inverted generally U-shaped portion, attached to said first flat portion, sufficiently sized for receiving said spanning bar; (c) a second generally horizontally disposed flat portion, attached to said inverted U-shaped portion, specifically configured to be received through a box knock-out opening formed in a wall of said electrical box, said second flat portion engaging an inner surface of said wall of said electrical box; and (d) initial holding means in the form of a tension leg for initially holding said clip in position on said electrical box before said clip is securely fastened to said electrical box.
 2. A clip as defined in claim 1, wherein said tension leg comprises: (a) a first portion extending generally upwardly from said second flat portion of said clip; (b) a second portion extending laterally outwardly and downwardly from said first portion of said tension leg; and (c) a third portion extending generally upwardly from a lower edge of said second portion of said tension leg.
 3. A clip as defined in claim 2, wherein said first, second and third portions of said tension leg and said second flat portion of said clip cooperate to form a channel means for receiving a peripheral edge of said knock-out opening in said wall of said electrical box.
 4. A clip as defined in claim 3, wherein the distance of separation between said lower edge of said second portion of said tension leg and said second flat portion of said clip is less than the thickness of said wall of said electrical box so that said lower edge resiliently engages said wall of said electrical box when said wall is received therein.
 5. A clip as defined in claim 1, wherein said clip further comprises load wire attachment means for receiving and engaging one or more load wires.
 6. A clip as defined in claim 5, wherein said load wire attachment means comprises a generally upwardly extending wire attachment arm and at least one wire attachment hole formed in said arm for receiving said one or more load wires.
 7. A clip as defined in claim 6, wherein said wire attachment arm extends generally upwardly from said inverted U-shaped portion of said clip.
 8. A clip as defined in claim 1, wherein said clip substantially covers said knock-out opening in said electrical box once installed.
 9. A bar hanger and mounting clip assembly for securing an electrical box between two opposed Tee bar elements in a ceiling structure, said clip assembly comprising: (a) a spanning bar which spans between said two opposed Tee bar elements; (b) first and second clips at opposed ends of said spanning bar for attaching said spanning bar to said two opposed Tee bar elements; (c) an electrical box; and (d) a mounting clip for securing said electrical box to said spanning bar, said mounting clip including initial holding means for initially holding said electrical box in position on said spanning bar before said clip is securely fastened to said electrical box.
 10. A bar hanger and mounting clip assembly as defined in claim 9, wherein said mounting clip comprises: (a) a first generally horizontally disposed flat portion engageable with an outer surface of said electrical box; (b) an inverted generally U-shaped portion, attached to said first flat portion, sufficiently sized for receiving said spanning bar; and (c) a second generally horizontally disposed flat portion, attached to said inverted U-shaped portion, specifically configured to be received through a box knock-out opening formed in a wall of said electrical box, said second flat portion engaging an inner surface of said wall of said electrical box.
 11. A bar hanger and mounting clip assembly as defined in claim 10, wherein said initial holding means comprises a tension leg which includes: (a) a first portion extending generally upwardly from said second flat portion of said mounting clip; (b) a second portion extending laterally outwardly and downwardly from said first portion of said tension leg; and (c) a third portion extending generally upwardly from a lower edge of said second portion of said tension leg.
 12. A bar hanger and mounting clip assembly as defined in claim 11, wherein said first, second and third portions of said tension leg and said second flat portion of said mounting clip cooperate to form a channel means for receiving a peripheral edge of said knock-out opening in said wall of said electrical box.
 13. A bar hanger and mounting clip assembly as defined in claim 12, wherein the distance of separation between said lower edge of said second portion of said tension leg and said second flat portion of said mounting clip is less than the thickness of said wall of said electrical box so that said lower edge resiliently engages said wall of said electrical box when said wall is received therein.
 14. A bar hanger and mounting clip assembly as defined in claim 9, wherein said clip further comprises load wire attachment means for receiving and engaging one or more load wires.
 15. A bar hanger and mounting clip assembly as defined in claim 14, wherein said load wire attachment means comprises a generally upwardly extending wire attachment arm and at least one wire attachment hole formed in said arm for receiving said one or more load wires.
 16. A bar hanger and mounting clip assembly as defined in claim 15, wherein said wire attachment arm extends generally upwardly from said inverted U-shaped portion of said clip.
 17. A bar hanger and mounting clip assembly as defined in claim 9, wherein said clip substantially covers said knock-out opening in said electrical box once installed. 